How to get control of soft crabgrass and spurge

chemingway4September 17, 2013

We bought a house in March of this year. At that time the lawn was beautiful! We decided to not pay to have a service take care of the lawn. We realized after a few mowings, that we were cutting the grass way to short. We adjusted the height to about 2" and it looked much better. We started to notice weeds so we did a treatment with Weed and Feed. Maybe it's me, but it seemed to make the problem worse. as you can see from the picture, its gotten pretty bad.
We have Bermuda grass, and the weeds we have are soft crabgrass and spurge, along with a few others, but the crabgrass is the worst. I didnt do any kind of fertilizing or preemergents in the spring (we had no idea). We water every other day for 16 minutes. There seems to be good drainage and no dead spots. So these are my questions: What do we do now? When do we do whatever we need to do? It's mid September, but still mid 80's. We do not want to kill off everything if at all possible. I feel like we can do the work ourselves, but we don't know what to do or what time of year to do it. If anyone has an idea, that wood be wonderful!!

Google "bermuda bible" and memorize it. It goes season by season for you.

You are watering almost exactly the opposite of what you should be doing. The only worse watering would be daily. You should be watering once every 2-3 weeks this time of year. Just changing your watering will kill some of your weeds. And in the spring, that watering regimen will stop the weed seeds which need to have daily water to sprout. That includes crabgrass. The watering mantra is deep and infrequent. Deep means one inch as measured by tuna or cat food cans placed around your yard while you water. Put some in dry spots and some in deep green spots to see how even your coverage is. Time how long it takes to fill all the cans. That is your starting target for watering. You can adjust from there. Do that now and see how long your bermuda can go without any more water. When it needs water, the bermuda will start to look dark green and foot prints will stay in the grass. Then water again a full inch. Generally the cooler it gets, the less evaporation and transpiration you get and the less often you need to water. I have a lawn next to the Texas desert that I have not watered in over a month with temps running in the high 90s and very little rain (about 3/4-inch). We have been blessed with daily clouds and an overabundance of humidity, so that must be keeping it going. But I have really deep roots in that grass. My point is you have to change your watering. And my other point is grass will adapt to infrequent watering by growing deep roots. And you have to test YOUR sprinkler system. Mine takes 8 full hours to fill the cans. My neighbor's fill in 20 minutes. Every system is different.

Crabgrass will die at the first frost of the season. You really don't need to do anything to make that happen.

Spurge will likely not simply go away by changing the watering. Weed-B-Gone spray should take that stuff out. WBG is a foliar spray, not a soil drench. Read the label for the temperature range for spraying it. It can set back your bermuda if it's too hot.